/*
---------------------------------------------------------------------------
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*/

/** @file  SMDLoader.cpp
 *  @brief Implementation of the SMD importer class
 */


#ifndef ASSIMP_BUILD_NO_SMD_IMPORTER

// internal headers
#include "SMDLoader.h"
#include "fast_atof.h"
#include "SkeletonMeshBuilder.h"
#include "../include/assimp/Importer.hpp"
#include "../include/assimp/IOSystem.hpp"
#include <boost/scoped_ptr.hpp>
#include "../include/assimp/scene.h"
#include "../include/assimp/DefaultLogger.hpp"


using namespace Assimp;

static const aiImporterDesc desc = {
    "Valve SMD Importer",
    "",
    "",
    "",
    aiImporterFlags_SupportTextFlavour,
    0,
    0,
    0,
    0,
    "smd vta"
};

// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
SMDImporter::SMDImporter()
{}

// ------------------------------------------------------------------------------------------------
// Destructor, private as well
SMDImporter::~SMDImporter()
{}

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file.
bool SMDImporter::CanRead( const std::string& pFile, IOSystem* /*pIOHandler*/, bool) const
{
    // fixme: auto format detection
    return SimpleExtensionCheck(pFile,"smd","vta");
}

// ------------------------------------------------------------------------------------------------
// Get a list of all supported file extensions
const aiImporterDesc* SMDImporter::GetInfo () const
{
    return &desc;
}

// ------------------------------------------------------------------------------------------------
// Setup configuration properties
void SMDImporter::SetupProperties(const Importer* pImp)
{
    // The
    // AI_CONFIG_IMPORT_SMD_KEYFRAME option overrides the
    // AI_CONFIG_IMPORT_GLOBAL_KEYFRAME option.
    configFrameID = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_SMD_KEYFRAME,-1);
    if(static_cast<unsigned int>(-1) == configFrameID)  {
        configFrameID = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_GLOBAL_KEYFRAME,0);
    }
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure.
void SMDImporter::InternReadFile( const std::string& pFile, aiScene* pScene, IOSystem* pIOHandler)
{
    boost::scoped_ptr<IOStream> file( pIOHandler->Open( pFile, "rb"));

    // Check whether we can read from the file
    if( file.get() == NULL) {
        throw DeadlyImportError( "Failed to open SMD/VTA file " + pFile + ".");
    }

    iFileSize = (unsigned int)file->FileSize();

    // Allocate storage and copy the contents of the file to a memory buffer
    this->pScene = pScene;

    std::vector<char> buff(iFileSize+1);
    TextFileToBuffer(file.get(),buff);
    mBuffer = &buff[0];

    iSmallestFrame = (1 << 31);
    bHasUVs = true;
    iLineNumber = 1;

    // Reserve enough space for ... hm ... 10 textures
    aszTextures.reserve(10);

    // Reserve enough space for ... hm ... 1000 triangles
    asTriangles.reserve(1000);

    // Reserve enough space for ... hm ... 20 bones
    asBones.reserve(20);


    // parse the file ...
    ParseFile();

    // If there are no triangles it seems to be an animation SMD,
    // containing only the animation skeleton.
    if (asTriangles.empty())
    {
        if (asBones.empty())
        {
            throw DeadlyImportError("SMD: No triangles and no bones have "
                "been found in the file. This file seems to be invalid.");
        }

        // Set the flag in the scene structure which indicates
        // that there is nothing than an animation skeleton
        pScene->mFlags |= AI_SCENE_FLAGS_INCOMPLETE;
    }

    if (!asBones.empty())
    {
        // Check whether all bones have been initialized
        for (std::vector<SMD::Bone>::const_iterator
            i =  asBones.begin();
            i != asBones.end();++i)
        {
            if (!(*i).mName.length())
            {
                DefaultLogger::get()->warn("SMD: Not all bones have been initialized");
                break;
            }
        }

        // now fix invalid time values and make sure the animation starts at frame 0
        FixTimeValues();

        // compute absolute bone transformation matrices
    //  ComputeAbsoluteBoneTransformations();
    }

    if (!(pScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE))
    {
        // create output meshes
        CreateOutputMeshes();

        // build an output material list
        CreateOutputMaterials();
    }

    // build the output animation
    CreateOutputAnimations();

    // build output nodes (bones are added as empty dummy nodes)
    CreateOutputNodes();

    if (pScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE)
    {
        SkeletonMeshBuilder skeleton(pScene);
    }
}
// ------------------------------------------------------------------------------------------------
// Write an error message with line number to the log file
void SMDImporter::LogErrorNoThrow(const char* msg)
{
    char szTemp[1024];
    sprintf(szTemp,"Line %u: %s",iLineNumber,msg);
    DefaultLogger::get()->error(szTemp);
}

// ------------------------------------------------------------------------------------------------
// Write a warning with line number to the log file
void SMDImporter::LogWarning(const char* msg)
{
    char szTemp[1024];
    ai_assert(strlen(msg) < 1000);
    sprintf(szTemp,"Line %u: %s",iLineNumber,msg);
    DefaultLogger::get()->warn(szTemp);
}

// ------------------------------------------------------------------------------------------------
// Fix invalid time values in the file
void SMDImporter::FixTimeValues()
{
    double dDelta = (double)iSmallestFrame;
    double dMax = 0.0f;
    for (std::vector<SMD::Bone>::iterator
        iBone =  asBones.begin();
        iBone != asBones.end();++iBone)
    {
        for (std::vector<SMD::Bone::Animation::MatrixKey>::iterator
            iKey =  (*iBone).sAnim.asKeys.begin();
            iKey != (*iBone).sAnim.asKeys.end();++iKey)
        {
            (*iKey).dTime -= dDelta;
            dMax = std::max(dMax, (*iKey).dTime);
        }
    }
    dLengthOfAnim = dMax;
}

// ------------------------------------------------------------------------------------------------
// create output meshes
void SMDImporter::CreateOutputMeshes()
{
    if (aszTextures.empty())
        aszTextures.push_back(std::string());

    // we need to sort all faces by their material index
    // in opposition to other loaders we can be sure that each
    // material is at least used once.
    pScene->mNumMeshes = (unsigned int) aszTextures.size();
    pScene->mMeshes = new aiMesh*[pScene->mNumMeshes];

    typedef std::vector<unsigned int> FaceList;
    FaceList* aaiFaces = new FaceList[pScene->mNumMeshes];

    // approximate the space that will be required
    unsigned int iNum = (unsigned int)asTriangles.size() / pScene->mNumMeshes;
    iNum += iNum >> 1;
    for (unsigned int i = 0; i < pScene->mNumMeshes;++i)
        aaiFaces[i].reserve(iNum);


    // collect all faces
    iNum = 0;
    for (std::vector<SMD::Face>::const_iterator
        iFace =  asTriangles.begin();
        iFace != asTriangles.end();++iFace,++iNum)
    {
        if (UINT_MAX == (*iFace).iTexture)aaiFaces[(*iFace).iTexture].push_back( 0 );
        else if ((*iFace).iTexture >= aszTextures.size())
        {
            DefaultLogger::get()->error("[SMD/VTA] Material index overflow in face");
            aaiFaces[(*iFace).iTexture].push_back((unsigned int)aszTextures.size()-1);
        }
        else aaiFaces[(*iFace).iTexture].push_back(iNum);
    }

    // now create the output meshes
    for (unsigned int i = 0; i < pScene->mNumMeshes;++i)
    {
        aiMesh*& pcMesh = pScene->mMeshes[i] = new aiMesh();
        ai_assert(!aaiFaces[i].empty()); // should not be empty ...

        pcMesh->mPrimitiveTypes = aiPrimitiveType_TRIANGLE;
        pcMesh->mNumVertices = (unsigned int)aaiFaces[i].size()*3;
        pcMesh->mNumFaces = (unsigned int)aaiFaces[i].size();
        pcMesh->mMaterialIndex = i;

        // storage for bones
        typedef std::pair<unsigned int,float> TempWeightListEntry;
        typedef std::vector< TempWeightListEntry > TempBoneWeightList;

        TempBoneWeightList* aaiBones = new TempBoneWeightList[asBones.size()]();

        // try to reserve enough memory without wasting too much
        for (unsigned int iBone = 0; iBone < asBones.size();++iBone)
        {
            aaiBones[iBone].reserve(pcMesh->mNumVertices/asBones.size());
        }

        // allocate storage
        pcMesh->mFaces = new aiFace[pcMesh->mNumFaces];
        aiVector3D* pcNormals = pcMesh->mNormals = new aiVector3D[pcMesh->mNumVertices];
        aiVector3D* pcVerts = pcMesh->mVertices = new aiVector3D[pcMesh->mNumVertices];

        aiVector3D* pcUVs = NULL;
        if (bHasUVs)
        {
            pcUVs = pcMesh->mTextureCoords[0] = new aiVector3D[pcMesh->mNumVertices];
            pcMesh->mNumUVComponents[0] = 2;
        }

        iNum = 0;
        for (unsigned int iFace = 0; iFace < pcMesh->mNumFaces;++iFace)
        {
            pcMesh->mFaces[iFace].mIndices = new unsigned int[3];
            pcMesh->mFaces[iFace].mNumIndices = 3;

            // fill the vertices
            unsigned int iSrcFace = aaiFaces[i][iFace];
            SMD::Face& face = asTriangles[iSrcFace];

            *pcVerts++ = face.avVertices[0].pos;
            *pcVerts++ = face.avVertices[1].pos;
            *pcVerts++ = face.avVertices[2].pos;

            // fill the normals
            *pcNormals++ = face.avVertices[0].nor;
            *pcNormals++ = face.avVertices[1].nor;
            *pcNormals++ = face.avVertices[2].nor;

            // fill the texture coordinates
            if (pcUVs)
            {
                *pcUVs++ = face.avVertices[0].uv;
                *pcUVs++ = face.avVertices[1].uv;
                *pcUVs++ = face.avVertices[2].uv;
            }

            for (unsigned int iVert = 0; iVert < 3;++iVert)
            {
                float fSum = 0.0f;
                for (unsigned int iBone = 0;iBone < face.avVertices[iVert].aiBoneLinks.size();++iBone)
                {
                    TempWeightListEntry& pairval = face.avVertices[iVert].aiBoneLinks[iBone];

                    // FIX: The second check is here just to make sure we won't
                    // assign more than one weight to a single vertex index
                    if (pairval.first >= asBones.size() ||
                        pairval.first == face.avVertices[iVert].iParentNode)
                    {
                        DefaultLogger::get()->error("[SMD/VTA] Bone index overflow. "
                            "The bone index will be ignored, the weight will be assigned "
                            "to the vertex' parent node");
                        continue;
                    }
                    aaiBones[pairval.first].push_back(TempWeightListEntry(iNum,pairval.second));
                    fSum += pairval.second;
                }
                // ******************************************************************
                // If the sum of all vertex weights is not 1.0 we must assign
                // the rest to the vertex' parent node. Well, at least the doc says
                // we should ...
                // FIX: We use 0.975 as limit, floating-point inaccuracies seem to
                // be very strong in some SMD exporters. Furthermore it is possible
                // that the parent of a vertex is 0xffffffff (if the corresponding
                // entry in the file was unreadable)
                // ******************************************************************
                if (fSum < 0.975f && face.avVertices[iVert].iParentNode != UINT_MAX)
                {
                    if (face.avVertices[iVert].iParentNode >= asBones.size())
                    {
                        DefaultLogger::get()->error("[SMD/VTA] Bone index overflow. "
                            "The index of the vertex parent bone is invalid. "
                            "The remaining weights will be normalized to 1.0");

                        if (fSum)
                        {
                            fSum = 1 / fSum;
                            for (unsigned int iBone = 0;iBone < face.avVertices[iVert].aiBoneLinks.size();++iBone)
                            {
                                TempWeightListEntry& pairval = face.avVertices[iVert].aiBoneLinks[iBone];
                                if (pairval.first >= asBones.size())continue;
                                aaiBones[pairval.first].back().second *= fSum;
                            }
                        }
                    }
                    else
                    {
                        aaiBones[face.avVertices[iVert].iParentNode].push_back(
                            TempWeightListEntry(iNum,1.0f-fSum));
                    }
                }
                pcMesh->mFaces[iFace].mIndices[iVert] = iNum++;
            }
        }

        // now build all bones of the mesh
        iNum = 0;
        for (unsigned int iBone = 0; iBone < asBones.size();++iBone)
            if (!aaiBones[iBone].empty())++iNum;

        if (false && iNum)
        {
            pcMesh->mNumBones = iNum;
            pcMesh->mBones = new aiBone*[pcMesh->mNumBones];
            iNum = 0;
            for (unsigned int iBone = 0; iBone < asBones.size();++iBone)
            {
                if (aaiBones[iBone].empty())continue;
                aiBone*& bone = pcMesh->mBones[iNum] = new aiBone();

                bone->mNumWeights = (unsigned int)aaiBones[iBone].size();
                bone->mWeights = new aiVertexWeight[bone->mNumWeights];
                bone->mOffsetMatrix = asBones[iBone].mOffsetMatrix;
                bone->mName.Set( asBones[iBone].mName );

                asBones[iBone].bIsUsed = true;

                for (unsigned int iWeight = 0; iWeight < bone->mNumWeights;++iWeight)
                {
                    bone->mWeights[iWeight].mVertexId = aaiBones[iBone][iWeight].first;
                    bone->mWeights[iWeight].mWeight = aaiBones[iBone][iWeight].second;
                }
                ++iNum;
            }
        }
        delete[] aaiBones;
    }
    delete[] aaiFaces;
}

// ------------------------------------------------------------------------------------------------
// add bone child nodes
void SMDImporter::AddBoneChildren(aiNode* pcNode, uint32_t iParent)
{
    ai_assert(NULL != pcNode && 0 == pcNode->mNumChildren && NULL == pcNode->mChildren);

    // first count ...
    for (unsigned int i = 0; i < asBones.size();++i)
    {
        SMD::Bone& bone = asBones[i];
        if (bone.iParent == iParent)++pcNode->mNumChildren;
    }

    // now allocate the output array
    pcNode->mChildren = new aiNode*[pcNode->mNumChildren];

    // and fill all subnodes
    unsigned int qq = 0;
    for (unsigned int i = 0; i < asBones.size();++i)
    {
        SMD::Bone& bone = asBones[i];
        if (bone.iParent != iParent)continue;

        aiNode* pc = pcNode->mChildren[qq++] = new aiNode();
        pc->mName.Set(bone.mName);

        // store the local transformation matrix of the bind pose
        pc->mTransformation = bone.sAnim.asKeys[bone.sAnim.iFirstTimeKey].matrix;
        pc->mParent = pcNode;

        // add children to this node, too
        AddBoneChildren(pc,i);
    }
}

// ------------------------------------------------------------------------------------------------
// create output nodes
void SMDImporter::CreateOutputNodes()
{
    pScene->mRootNode = new aiNode();
    if (!(pScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE))
    {
        // create one root node that renders all meshes
        pScene->mRootNode->mNumMeshes = pScene->mNumMeshes;
        pScene->mRootNode->mMeshes = new unsigned int[pScene->mNumMeshes];
        for (unsigned int i = 0; i < pScene->mNumMeshes;++i)
            pScene->mRootNode->mMeshes[i] = i;
    }

    // now add all bones as dummy sub nodes to the graph
    // AddBoneChildren(pScene->mRootNode,(uint32_t)-1);

    // if we have only one bone we can even remove the root node
    if (pScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE &&
        1 == pScene->mRootNode->mNumChildren)
    {
        aiNode* pcOldRoot = pScene->mRootNode;
        pScene->mRootNode = pcOldRoot->mChildren[0];
        pcOldRoot->mChildren[0] = NULL;
        delete pcOldRoot;

        pScene->mRootNode->mParent = NULL;
    }
    else
    {
        ::strcpy(pScene->mRootNode->mName.data, "<SMD_root>");
        pScene->mRootNode->mName.length = 10;
    }
}

// ------------------------------------------------------------------------------------------------
// create output animations
void SMDImporter::CreateOutputAnimations()
{
    unsigned int iNumBones = 0;
    for (std::vector<SMD::Bone>::const_iterator
        i =  asBones.begin();
        i != asBones.end();++i)
    {
        if ((*i).bIsUsed)++iNumBones;
    }
    if (!iNumBones)
    {
        // just make sure this case doesn't occur ... (it could occur
        // if the file was invalid)
        return;
    }

    pScene->mNumAnimations = 1;
    pScene->mAnimations = new aiAnimation*[1];
    aiAnimation*& anim = pScene->mAnimations[0] = new aiAnimation();

    anim->mDuration = dLengthOfAnim;
    anim->mNumChannels = iNumBones;
    anim->mTicksPerSecond = 25.0; // FIXME: is this correct?

    aiNodeAnim** pp = anim->mChannels = new aiNodeAnim*[anim->mNumChannels];

    // now build valid keys
    unsigned int a = 0;
    for (std::vector<SMD::Bone>::const_iterator
        i =  asBones.begin();
        i != asBones.end();++i)
    {
        if (!(*i).bIsUsed)continue;

        aiNodeAnim* p = pp[a] = new aiNodeAnim();

        // copy the name of the bone
        p->mNodeName.Set( i->mName);

        p->mNumRotationKeys = (unsigned int) (*i).sAnim.asKeys.size();
        if (p->mNumRotationKeys)
        {
            p->mNumPositionKeys = p->mNumRotationKeys;
            aiVectorKey* pVecKeys = p->mPositionKeys = new aiVectorKey[p->mNumRotationKeys];
            aiQuatKey* pRotKeys = p->mRotationKeys = new aiQuatKey[p->mNumRotationKeys];

            for (std::vector<SMD::Bone::Animation::MatrixKey>::const_iterator
                qq =  (*i).sAnim.asKeys.begin();
                qq != (*i).sAnim.asKeys.end(); ++qq)
            {
                pRotKeys->mTime = pVecKeys->mTime = (*qq).dTime;

                // compute the rotation quaternion from the euler angles
                pRotKeys->mValue = aiQuaternion( (*qq).vRot.x, (*qq).vRot.y, (*qq).vRot.z );
                pVecKeys->mValue = (*qq).vPos;

                ++pVecKeys; ++pRotKeys;
            }
        }
        ++a;

        // there are no scaling keys ...
    }
}

// ------------------------------------------------------------------------------------------------
void SMDImporter::ComputeAbsoluteBoneTransformations()
{
    // For each bone: determine the key with the lowest time value
    // theoretically the SMD format should have all keyframes
    // in order. However, I've seen a file where this wasn't true.
    for (unsigned int i = 0; i < asBones.size();++i)
    {
        SMD::Bone& bone = asBones[i];

        uint32_t iIndex = 0;
        double dMin = 10e10;
        for (unsigned int i = 0; i < bone.sAnim.asKeys.size();++i)
        {
            double d = std::min(bone.sAnim.asKeys[i].dTime,dMin);
            if (d < dMin)
            {
                dMin = d;
                iIndex = i;
            }
        }
        bone.sAnim.iFirstTimeKey = iIndex;
    }

    unsigned int iParent = 0;
    while (iParent < asBones.size())
    {
        for (unsigned int iBone = 0; iBone < asBones.size();++iBone)
        {
            SMD::Bone& bone = asBones[iBone];

            if (iParent == bone.iParent)
            {
                SMD::Bone& parentBone = asBones[iParent];


                uint32_t iIndex = bone.sAnim.iFirstTimeKey;
                const aiMatrix4x4& mat = bone.sAnim.asKeys[iIndex].matrix;
                aiMatrix4x4& matOut = bone.sAnim.asKeys[iIndex].matrixAbsolute;

                // The same for the parent bone ...
                iIndex = parentBone.sAnim.iFirstTimeKey;
                const aiMatrix4x4& mat2 = parentBone.sAnim.asKeys[iIndex].matrixAbsolute;

                // Compute the absolute transformation matrix
                matOut = mat * mat2;
            }
        }
        ++iParent;
    }

    // Store the inverse of the absolute transformation matrix
    // of the first key as bone offset matrix
    for (iParent = 0; iParent < asBones.size();++iParent)
    {
        SMD::Bone& bone = asBones[iParent];
        bone.mOffsetMatrix = bone.sAnim.asKeys[bone.sAnim.iFirstTimeKey].matrixAbsolute;
        bone.mOffsetMatrix.Inverse();
    }
}

// ------------------------------------------------------------------------------------------------
// create output materials
void SMDImporter::CreateOutputMaterials()
{
    pScene->mNumMaterials = (unsigned int)aszTextures.size();
    pScene->mMaterials = new aiMaterial*[std::max(1u, pScene->mNumMaterials)];

    for (unsigned int iMat = 0; iMat < pScene->mNumMaterials;++iMat)
    {
        aiMaterial* pcMat = new aiMaterial();
        pScene->mMaterials[iMat] = pcMat;

        aiString szName;
        szName.length = (size_t)::sprintf(szName.data,"Texture_%u",iMat);
        pcMat->AddProperty(&szName,AI_MATKEY_NAME);

        if (aszTextures[iMat].length())
        {
            ::strcpy(szName.data, aszTextures[iMat].c_str() );
            szName.length = aszTextures[iMat].length();
            pcMat->AddProperty(&szName,AI_MATKEY_TEXTURE_DIFFUSE(0));
        }
    }

    // create a default material if necessary
    if (0 == pScene->mNumMaterials)
    {
        pScene->mNumMaterials = 1;

        aiMaterial* pcHelper = new aiMaterial();
        pScene->mMaterials[0] = pcHelper;

        int iMode = (int)aiShadingMode_Gouraud;
        pcHelper->AddProperty<int>(&iMode, 1, AI_MATKEY_SHADING_MODEL);

        aiColor3D clr;
        clr.b = clr.g = clr.r = 0.7f;
        pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_DIFFUSE);
        pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_SPECULAR);

        clr.b = clr.g = clr.r = 0.05f;
        pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_AMBIENT);

        aiString szName;
        szName.Set(AI_DEFAULT_MATERIAL_NAME);
        pcHelper->AddProperty(&szName,AI_MATKEY_NAME);
    }
}

// ------------------------------------------------------------------------------------------------
// Parse the file
void SMDImporter::ParseFile()
{
    const char* szCurrent = mBuffer;

    // read line per line ...
    for ( ;; )
    {
        if(!SkipSpacesAndLineEnd(szCurrent,&szCurrent)) break;

        // "version <n> \n", <n> should be 1 for hl and hlČ SMD files
        if (TokenMatch(szCurrent,"version",7))
        {
            if(!SkipSpaces(szCurrent,&szCurrent)) break;
            if (1 != strtoul10(szCurrent,&szCurrent))
            {
                DefaultLogger::get()->warn("SMD.version is not 1. This "
                    "file format is not known. Continuing happily ...");
            }
            continue;
        }
        // "nodes\n" - Starts the node section
        if (TokenMatch(szCurrent,"nodes",5))
        {
            ParseNodesSection(szCurrent,&szCurrent);
            continue;
        }
        // "triangles\n" - Starts the triangle section
        if (TokenMatch(szCurrent,"triangles",9))
        {
            ParseTrianglesSection(szCurrent,&szCurrent);
            continue;
        }
        // "vertexanimation\n" - Starts the vertex animation section
        if (TokenMatch(szCurrent,"vertexanimation",15))
        {
            bHasUVs = false;
            ParseVASection(szCurrent,&szCurrent);
            continue;
        }
        // "skeleton\n" - Starts the skeleton section
        if (TokenMatch(szCurrent,"skeleton",8))
        {
            ParseSkeletonSection(szCurrent,&szCurrent);
            continue;
        }
        SkipLine(szCurrent,&szCurrent);
    }
    return;
}

// ------------------------------------------------------------------------------------------------
unsigned int SMDImporter::GetTextureIndex(const std::string& filename)
{
    unsigned int iIndex = 0;
    for (std::vector<std::string>::const_iterator
        i =  aszTextures.begin();
        i != aszTextures.end();++i,++iIndex)
    {
        // case-insensitive ... it's a path
        if (0 == ASSIMP_stricmp ( filename.c_str(),(*i).c_str()))return iIndex;
    }
    iIndex = (unsigned int)aszTextures.size();
    aszTextures.push_back(filename);
    return iIndex;
}

// ------------------------------------------------------------------------------------------------
// Parse the nodes section of the file
void SMDImporter::ParseNodesSection(const char* szCurrent,
    const char** szCurrentOut)
{
    for ( ;; )
    {
        // "end\n" - Ends the nodes section
        if (0 == ASSIMP_strincmp(szCurrent,"end",3) &&
            IsSpaceOrNewLine(*(szCurrent+3)))
        {
            szCurrent += 4;
            break;
        }
        ParseNodeInfo(szCurrent,&szCurrent);
    }
    SkipSpacesAndLineEnd(szCurrent,&szCurrent);
    *szCurrentOut = szCurrent;
}

// ------------------------------------------------------------------------------------------------
// Parse the triangles section of the file
void SMDImporter::ParseTrianglesSection(const char* szCurrent,
    const char** szCurrentOut)
{
    // Parse a triangle, parse another triangle, parse the next triangle ...
    // and so on until we reach a token that looks quite similar to "end"
    for ( ;; )
    {
        if(!SkipSpacesAndLineEnd(szCurrent,&szCurrent)) break;

        // "end\n" - Ends the triangles section
        if (TokenMatch(szCurrent,"end",3))
            break;
        ParseTriangle(szCurrent,&szCurrent);
    }
    SkipSpacesAndLineEnd(szCurrent,&szCurrent);
    *szCurrentOut = szCurrent;
}
// ------------------------------------------------------------------------------------------------
// Parse the vertex animation section of the file
void SMDImporter::ParseVASection(const char* szCurrent,
    const char** szCurrentOut)
{
    unsigned int iCurIndex = 0;
    for ( ;; )
    {
        if(!SkipSpacesAndLineEnd(szCurrent,&szCurrent)) break;

        // "end\n" - Ends the "vertexanimation" section
        if (TokenMatch(szCurrent,"end",3))
            break;

        // "time <n>\n"
        if (TokenMatch(szCurrent,"time",4))
        {
            // NOTE: The doc says that time values COULD be negative ...
            // NOTE2: this is the shape key -> valve docs
            int iTime = 0;
            if(!ParseSignedInt(szCurrent,&szCurrent,iTime) || configFrameID != (unsigned int)iTime)break;
            SkipLine(szCurrent,&szCurrent);
        }
        else
        {
            if(0 == iCurIndex)
            {
                asTriangles.push_back(SMD::Face());
            }
            if (++iCurIndex == 3)iCurIndex = 0;
            ParseVertex(szCurrent,&szCurrent,asTriangles.back().avVertices[iCurIndex],true);
        }
    }

    if (iCurIndex != 2 && !asTriangles.empty())
    {
        // we want to no degenerates, so throw this triangle away
        asTriangles.pop_back();
    }

    SkipSpacesAndLineEnd(szCurrent,&szCurrent);
    *szCurrentOut = szCurrent;
}
// ------------------------------------------------------------------------------------------------
// Parse the skeleton section of the file
void SMDImporter::ParseSkeletonSection(const char* szCurrent,
    const char** szCurrentOut)
{
    int iTime = 0;
    for ( ;; )
    {
        if(!SkipSpacesAndLineEnd(szCurrent,&szCurrent)) break;

        // "end\n" - Ends the skeleton section
        if (TokenMatch(szCurrent,"end",3))
            break;

        // "time <n>\n" - Specifies the current animation frame
        else if (TokenMatch(szCurrent,"time",4))
        {
            // NOTE: The doc says that time values COULD be negative ...
            if(!ParseSignedInt(szCurrent,&szCurrent,iTime))break;

            iSmallestFrame = std::min(iSmallestFrame,iTime);
            SkipLine(szCurrent,&szCurrent);
        }
        else ParseSkeletonElement(szCurrent,&szCurrent,iTime);
    }
    *szCurrentOut = szCurrent;
}

// ------------------------------------------------------------------------------------------------
#define SMDI_PARSE_RETURN { \
    SkipLine(szCurrent,&szCurrent); \
    *szCurrentOut = szCurrent; \
    return; \
}
// ------------------------------------------------------------------------------------------------
// Parse a node line
void SMDImporter::ParseNodeInfo(const char* szCurrent,
    const char** szCurrentOut)
{
    unsigned int iBone  = 0;
    SkipSpacesAndLineEnd(szCurrent,&szCurrent);
    if(!ParseUnsignedInt(szCurrent,&szCurrent,iBone) || !SkipSpaces(szCurrent,&szCurrent))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing bone index");
        SMDI_PARSE_RETURN;
    }
    // add our bone to the list
    if (iBone >= asBones.size())asBones.resize(iBone+1);
    SMD::Bone& bone = asBones[iBone];

    bool bQuota = true;
    if ('\"' != *szCurrent)
    {
        LogWarning("Bone name is expcted to be enclosed in "
            "double quotation marks. ");
        bQuota = false;
    }
    else ++szCurrent;

    const char* szEnd = szCurrent;
    for ( ;; )
    {
        if (bQuota && '\"' == *szEnd)
        {
            iBone = (unsigned int)(szEnd - szCurrent);
            ++szEnd;
            break;
        }
        else if (IsSpaceOrNewLine(*szEnd))
        {
            iBone = (unsigned int)(szEnd - szCurrent);
            break;
        }
        else if (!(*szEnd))
        {
            LogErrorNoThrow("Unexpected EOF/EOL while parsing bone name");
            SMDI_PARSE_RETURN;
        }
        ++szEnd;
    }
    bone.mName = std::string(szCurrent,iBone);
    szCurrent = szEnd;

    // the only negative bone parent index that could occur is -1 AFAIK
    if(!ParseSignedInt(szCurrent,&szCurrent,(int&)bone.iParent))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing bone parent index. Assuming -1");
        SMDI_PARSE_RETURN;
    }

    // go to the beginning of the next line
    SMDI_PARSE_RETURN;
}

// ------------------------------------------------------------------------------------------------
// Parse a skeleton element
void SMDImporter::ParseSkeletonElement(const char* szCurrent,
    const char** szCurrentOut,int iTime)
{
    aiVector3D vPos;
    aiVector3D vRot;

    unsigned int iBone  = 0;
    if(!ParseUnsignedInt(szCurrent,&szCurrent,iBone))
    {
        DefaultLogger::get()->error("Unexpected EOF/EOL while parsing bone index");
        SMDI_PARSE_RETURN;
    }
    if (iBone >= asBones.size())
    {
        LogErrorNoThrow("Bone index in skeleton section is out of range");
        SMDI_PARSE_RETURN;
    }
    SMD::Bone& bone = asBones[iBone];

    bone.sAnim.asKeys.push_back(SMD::Bone::Animation::MatrixKey());
    SMD::Bone::Animation::MatrixKey& key = bone.sAnim.asKeys.back();

    key.dTime = (double)iTime;
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vPos.x))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.pos.x");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vPos.y))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.pos.y");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vPos.z))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.pos.z");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vRot.x))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.rot.x");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vRot.y))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.rot.y");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vRot.z))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.rot.z");
        SMDI_PARSE_RETURN;
    }
    // build the transformation matrix of the key
    key.matrix.FromEulerAnglesXYZ(vRot.x,vRot.y,vRot.z);
    {
        aiMatrix4x4 mTemp;
        mTemp.a4 = vPos.x;
        mTemp.b4 = vPos.y;
        mTemp.c4 = vPos.z;
        key.matrix = key.matrix * mTemp;
    }

    // go to the beginning of the next line
    SMDI_PARSE_RETURN;
}

// ------------------------------------------------------------------------------------------------
// Parse a triangle
void SMDImporter::ParseTriangle(const char* szCurrent,
    const char** szCurrentOut)
{
    asTriangles.push_back(SMD::Face());
    SMD::Face& face = asTriangles.back();

    if(!SkipSpaces(szCurrent,&szCurrent))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing a triangle");
        return;
    }

    // read the texture file name
    const char* szLast = szCurrent;
    while (!IsSpaceOrNewLine(*szCurrent++));

    // ... and get the index that belongs to this file name
    face.iTexture = GetTextureIndex(std::string(szLast,(uintptr_t)szCurrent-(uintptr_t)szLast));

    SkipSpacesAndLineEnd(szCurrent,&szCurrent);

    // load three vertices
    for (unsigned int iVert = 0; iVert < 3;++iVert)
    {
        ParseVertex(szCurrent,&szCurrent,
            face.avVertices[iVert]);
    }
    *szCurrentOut = szCurrent;
}

// ------------------------------------------------------------------------------------------------
// Parse a float
bool SMDImporter::ParseFloat(const char* szCurrent,
    const char** szCurrentOut, float& out)
{
    if(!SkipSpaces(&szCurrent))
        return false;

    *szCurrentOut = fast_atoreal_move<float>(szCurrent,out);
    return true;
}

// ------------------------------------------------------------------------------------------------
// Parse an unsigned int
bool SMDImporter::ParseUnsignedInt(const char* szCurrent,
    const char** szCurrentOut, unsigned int& out)
{
    if(!SkipSpaces(&szCurrent))
        return false;

    out = strtoul10(szCurrent,szCurrentOut);
    return true;
}

// ------------------------------------------------------------------------------------------------
// Parse a signed int
bool SMDImporter::ParseSignedInt(const char* szCurrent,
    const char** szCurrentOut, int& out)
{
    if(!SkipSpaces(&szCurrent))
        return false;

    out = strtol10(szCurrent,szCurrentOut);
    return true;
}

// ------------------------------------------------------------------------------------------------
// Parse a vertex
void SMDImporter::ParseVertex(const char* szCurrent,
    const char** szCurrentOut, SMD::Vertex& vertex,
    bool bVASection /*= false*/)
{
    if (SkipSpaces(&szCurrent) && IsLineEnd(*szCurrent))
    {
        SkipSpacesAndLineEnd(szCurrent,&szCurrent);
        return ParseVertex(szCurrent,szCurrentOut,vertex,bVASection);
    }
    if(!ParseSignedInt(szCurrent,&szCurrent,(int&)vertex.iParentNode))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.parent");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.pos.x))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.pos.x");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.pos.y))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.pos.y");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.pos.z))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.pos.z");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.nor.x))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.nor.x");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.nor.y))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.nor.y");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.nor.z))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.nor.z");
        SMDI_PARSE_RETURN;
    }

    if (bVASection)SMDI_PARSE_RETURN;

    if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.uv.x))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.uv.x");
        SMDI_PARSE_RETURN;
    }
    if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.uv.y))
    {
        LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.uv.y");
        SMDI_PARSE_RETURN;
    }

    // now read the number of bones affecting this vertex
    // all elements from now are fully optional, we don't need them
    unsigned int iSize = 0;
    if(!ParseUnsignedInt(szCurrent,&szCurrent,iSize))SMDI_PARSE_RETURN;
    vertex.aiBoneLinks.resize(iSize,std::pair<unsigned int, float>(0,0.0f));

    for (std::vector<std::pair<unsigned int, float> >::iterator
        i =  vertex.aiBoneLinks.begin();
        i != vertex.aiBoneLinks.end();++i)
    {
        if(!ParseUnsignedInt(szCurrent,&szCurrent,(*i).first))
            SMDI_PARSE_RETURN;
        if(!ParseFloat(szCurrent,&szCurrent,(*i).second))
            SMDI_PARSE_RETURN;
    }

    // go to the beginning of the next line
    SMDI_PARSE_RETURN;
}

#endif // !! ASSIMP_BUILD_NO_SMD_IMPORTER